Motorless Treadmill with Large Flywheel

ABSTRACT

A motorless exercise treadmill has a flywheel of 7 to 10 inches radius, weighing 40 to 60 pounds. The flywheel provides a fluid motion for the belt when the brake system is engaged and smooth transition through increasing or decreasing speeds. Inclination of the treadmill is fixed at 9 to 20 degrees, which accommodates the large size of the flywheel. Handle and other attachments of different designs are provided so the user can exercise in various positions with various resistance levels for developing specific leg, core, arm and other muscles, not normally achievable on a treadmill.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the full benefit of U.S. Provisional Application61/782,998 filed Mar. 14, 2013 and U.S. Provisional Application61/858,854 filed Jul. 26, 2013, both of which are hereby incorporatedherein by reference in their entireties.

TECHNICAL FIELD

The invention relates to exercise treadmills. In particular, it relatesto motorless treadmills—that is, treadmills powered by the user. Handleand other attachments of different designs are provided so the user canexercise in various positions with various resistance levels fordeveloping specific leg, core, arm and other muscles. A large flywheelof a particular design is arranged to provide a fluid motion for thebelt when the brake system is engaged and smooth transition throughincreasing or decreasing speeds. Inclination of the treadmill is fixed.

BACKGROUND OF THE INVENTION

Generally, treadmills are powered by a motor and are used mainly foraerobic (cardiac) exercise such as walking and running, but providelittle or no possibility of simultaneous specific or varied musclestrengthening regimes with resistance training. Some elliptical machinesare designed to strengthen leg muscles, but must be further equipped ifthey are to exercise the arms, upper body and other muscles. Equippingan exercise machine of any kind with a motor adds significant cost,operating expense, liability, and limited mobility. The art is in needof an affordable highly versatile exercise machine.

SUMMARY OF THE INVENTION

The present invention is a manually powered inclined treadmill withvarious levels of resistance. The conventional motor is replaced with alarge heavy weighted flywheel, obviating the expense and maintenancenecessitated by a motor. The motor is replaced with a 40-60 poundflywheel having a large diameter and other attributes explained below,which captures the energy of the belt motion. The flywheel keeps thebelt in motion, and maintains a fluid motion through transitions ofresistance and speed. A brake effect may be applied to the flywheel atthe discretion of the user. The brake system when applied createsresistance on the flywheel, enabling the user to enhance a strengthprofile. The resistance to the flywheel is applied incrementally,affording the user with a wide range of resistance levels. In order togenerate the desired moment of inertia, the large diameter flywheel mustcontain a high percentage of its mass, or weight, toward its outer edge.Since the user must use muscle power entirely to move the inclined beltand the treadmill can have various levels of resistance applied, he orshe simulates actual incline climbing more effectively than when thebelt is powered by a motor, burning more calories and effecting greatermuscle stimulation.

The motorless, inclined treadmill is designed to be a crossover between(that is, to incorporate the benefits of) an inclined treadmill and anelliptical. It offers the cardio benefits of a treadmill motion with themuscle stimulation of elliptical, while enabling variable resistancelevels and facilitating arm, shoulder and upper body muscle developmentas well as providing significant leg muscle challenges. It is equippedwith multiple vertical and horizontal hand stations so the user canposition himself or herself into various postures simulating anelliptical motion, a football sled, or other regimes not readilyavailable with other types of exercise machines.

Solidly attached to the frame of my treadmill is an elongated socketadapted to receive elongated stems or shafts for a variety of handlesand pressure surfaces which may be used at different heights and with awide variety of speed and resistance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an exerciser on the treadmill usingan arm rest attachment.

FIG. 2 illustrates an exercise position on the treadmill different fromthat of FIG. 1, employing a different front attachment.

FIG. 3 shows the treadmill equipped for using the shoulders to push.

FIG. 4 shows a front attachment that facilitates a forward leaningposition, enabling a longer stride.

FIG. 5 shows the braking device.

FIG. 6 is a graph showing speed change of the perimeter weightedtreadmill over a single stride at different speeds and at variousinclinations.

FIG. 7 is a graph showing force required to maintain a constant speed atvarious inclinations.

FIGS. 8 a to 8 f illustrate the treadmill with separated attachments.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, the treadmill is seen to have a continuoustreadmill belt 1 forming a treadmill exercise surface 2 and supported byfront roller 3 and back roller 4, which are mounted in frame 5. Exercisesurface 2 of treadmill belt 1 rides on a support surface (not shown) asis known in the art. Frame 5 rests on feet 14. Attachment support socket6 is fixed to the front of frame 5. Attachment socket 6 is hollow andmay be cylindrical or define a square or other cross section in order toreceive snugly the stem 7 of an accessory positioner 8. Accessorypositioner 8 has a particular shape and configuration, in this caseincluding an arm rest portion 15, but other, interchangeable, accessorypositioners may have different shapes and configuration as will beexplained below. Attachment socket 6 is provided with holes 9 so thatpins 10 can pass through them and through complementary holes 11 on stem7 and similar stems for other accessory positioners. As depicted in FIG.1, user 16 is resting her arms on arm rest portion 15 of accessorypositioner 8 and grasps handles 17. She is thus able to exertsignificant forward thrust on the treadmill exercise surface 2. Frontroller 3 is turned by the treadmill belt 1 and, since flywheel 12 isfixed to front roller 3, the flywheel 12 will rotate in a clockwisedirection, as depicted. The significant moment of inertia of theperimeter weighted flywheel soon assures a smooth continuous movement ofthe treadmill belt 1. User 16 is able to regulate the application ofresistance to flywheel 12 by manipulating resistance control 13 at anytime.

Flywheel 12 is a perimeter weighted flywheel fixed to rotate with frontroller 3, the flywheel 12 having a radius of 7 to 10 inches and a massof 40 to 60 pounds; in this case, it has a radius of 8inches and a massof 55 pounds.

For a flat disc of any thickness and even weight distribution, there isa constant relationship between the peripheral weight and the totalweight. In Table 1, the relationship is laid out:

Table 1—percent of weight in the periphery of a disc flywheel of evenlydistributed weight, measured at various distances from the center, wherer is the radius:

Outside 0.6r: 64%

Outside 0.7r: 51%

Outside 0.8r: 36%

Outside 0.9r: 19%

These percentages are true for a flywheel having evenly distributedweight of any radius, but my invention calls for a radius of 7 to 10inches. This means, for example, that a plain, evenly distributed massflywheel of my minimum radius 7 will have 51% of its weight in the areaoutside 4.9 inches radius (0.7r). At my maximum radius of 10 inches (aswith a 7 inch disc), all of the above percentages apply. My criteriaalso call for a mass of 40 to 60 pounds for the flywheel as a whole.Thus a 55 pound, 8 inch flywheel will have 0.36×55, or 19.8, pounds inthe area defined by the outside (near the edge) 1.6 inches of radius; ofcourse it will satisfy all the other percentages of Table 1 also. Aflywheel of less than 7 inches radius will not have any mass at all thatfar from its rotation center.

Persons skilled in the art will recognize that flywheels need not beplain, evenly distributed discs. For example, they may be hollowed outin the center or thin in various patterns, or may be completely open incertain areas to define spokes or spoke-like members. Such types ofconstruction which may tend to reduce the amount of weight near thecenter of the flywheel relative to that near the perimeter are useful inmy invention, so long as the total weight and radius criteria are met.The flywheel should not be of a shape or construction which distributesweight with an uneven bias toward the center of the flywheel; it must beat least evenly distributed or perimeter weighted. By “perimeterweighted” is meant that the average of the centers of gravity for allradii is located farther toward the perimeter than 0.5r, where r is theradius—that is, the flywheel may have an uneven bias of weight towardthe periphery.

Persons skilled in the art will also recognize that the rollers orspindles on which the belt turns also have a modest flywheel effect. Asdiscussed above, flywheel 12 is attached or fixed directly onto frontroller 3 so they turn together. Although the roller 3 has a modestflywheel effect, my criteria for the flywheel do not consider it, nor dothey consider that the center of the flywheel may be open—that is,completely absent—so the end of front roller 3 can be inserted into itas shown. Thus, a flywheel meeting my criteria of 40 to 60 pounds andhaving a radius of 7 to 10 inches will include such a flywheel.

The flywheel 12 may be in the form and placement illustrated or may besplit into two perimeter weighted flywheel parts, one on each end offront roller 3, each having a radius of 7 to 10 inches and each havinghalf of a total of 40 to 60 pounds. I consider this arrangement a singleflywheel. In either case—whether the flywheel 12 is on one end of theroller or two, as shown or split, with one part on each end of frontroller 3, its large diameter is accommodated by the overall inclinationof the treadmill. As indicated by the difference in length between frontlegs 18 and rear legs 19, frame 5 and treadmill surface 2 are maintainedat an angle from 9 to 20 degrees. In the case of FIG. 1, the angle is 12degrees, as an angle of 11 to 13 degrees is preferred. Side rails 20 arean optional safety feature.

In FIG. 2, unlike the stance of the user in FIG. 1, the exerciserassumes a more upright position but grasps handles 21 of attachment 22which has been inserted into support socket 6, secured by pins 10.Resistance control 13 of FIG. 1 has been replaced by knob 30 for varyingresistance on flywheel 12, as will be further explained with referenceto

FIG. 5. Otherwise the treadmill is identical to the one depicted in FIG.1, comprising frame 5, treadmill belt 1, and flywheel 12. Front legs 18and rear legs 19 are of different lengths in order to provide a slope of11 degrees for the treadmill surface 2.

In FIG. 3, the basic treadmill is also similar to that of FIGS. 1 and 2,comprising frame 5, treadmill belt 1, and flywheel 12. In this case,however, front legs 18 and rear legs 19 are of different lengths inorder to provide a slope of 13 degrees for the treadmill surface 2. Butalso, attachment support 25 holds a crosspiece 26 to which are attachedtwo reinforced pads 27 adapted for contact with the user's shoulders.Handles 28 in this case extend downwardly and outwardly so the user canexert part of his strength on them if desired. Insert 29 snugly receivesattachment support 25 at its upper end. Handles 28 are welded orotherwise firmly attached to insert 29, which fits into attachmentsocket 6 in a manner similar to the way stem 7 fits into attachmentsocket 6 in FIG. 1. With an appropriate resistance adjustment appliedthrough brake bracket 13, the resultant “uphill” exertion simulates afootball exercise device. It should be noted that, since the treadmilldoes not require electricity, it may be placed on an athletic field oranywhere remote from an electrical outlet.

The user in FIG. 4 has chosen to employ insert 29 and its handles 28without using attachment support 25 or the reinforced pads 27 of FIG. 3.She assumes a more forward leaning posture than the user in FIG. 3,pushing only on the handles 28, and is able to take longer strides thanthe user in FIG. 3, who has chosen to exert the most force on reinforcedpads 27. The treadmill of FIG. 4 is otherwise similar to the treadmillsof FIGS. 1, 2, and 3, comprising treadmill belt 1, frame 5, and flywheel12. The fixed inclination of the treadmill in FIG. 4 is 12 degrees.

Since it is an object of the invention to eliminate the expense of amotor, it is important to understand the effect of the fixed, rathersteep, inclination of the treadmill. Not having a motor, there is no wayto change the inclination of the treadmill using external power. Ofcourse, one can simply prop up the front of the treadmill by placing atemporary platform under front legs 18 if additional slope is desired.The invention does not require a variable slope, but if for some reasonone would want to incorporate a motor to vary the slope, it could beaccommodated without changing the basic relationship between the size ofthe flywheel and the slope of the treadmill.

As indicated elsewhere herein, the flywheel should have an outsidediameter of 14 to 20 inches, and therefore the front of the treadmillmust be high enough for it to turn freely. As also indicated elsewhere,its mass should be within a range of 40 to 60 pounds. Some of theeffects of the heavy large-diameter, perimeter weighted, flywheel areshown in the graphs in FIGS. 6 and 7. They are based on an arbitrarilyselected value of 24.5 kg (54.2 pounds) for the flywheel assumed to beconcentrated entirely in the form of a torus. Where the radius of thetorus from its center to the middle of the ring on the other side is0.2285 meter (9 inches) and the radius within the torus body, or tube,is assumed to be zero, applying the formula I=½mr² where r is the radiusof the torus (taken from its center to the center of the cross sectionof the torus tube, which is assumed to have a radius of zero), and m isthe mass of the torus, yields a mass moment of inertia I=0.64. Thisnumber is used to develop the information in the following paragraphs.

The exponential effect of the deliberately chosen long radius of theflywheel results in an aggressive inertia. The inertia created by thelarge perimeter weighted flywheel allows the tread belt to move smoothlyunder heavy resistance by the braking system. If such inertia is notcreated then the user would experience a stop and start action of thetread belt while under resistance by the braking system.

In a sense, all treadmills have fly wheels, motorized and non motorized.Even where there is no device called a flywheel, the rollers or spindleson which the belt turns store a certain amount of energy as they areturned. It is a natural function of moving the tread belt. But theprevious designs of the flywheels have been much smaller and weights aretypically in the range of 10 to 18 pounds in wheels of smallerdimensions. My design is much different. The size and weight differs butthe function is the key. My flywheel is designed to distribute asignificant weight at longer distances from the center and generallymore than half way to the edge, a technique which may be called“perimeter weighting.” The perimeter weighting, size of the OD (outsidediameter) and heavy weight all contribute to the principle of aggressiveinertia which I employ. The aggressive inertia drives the tread belt ina way similar to a motorized driven unit. No other treadmill employs myprinciple of aggressive inertia and perimeter weighting.

In FIG. 5, the mechanism of the brake is shown. Brake base 40 is mountedon pivot 41 and is integral to plate 42 through which an elongate screw43 passes. Brake pad 44 lines the concave surface of brake base 40.Brake base 40 and brake pad 44 are positioned in relation to pivot 41and plate 42 so that the end of brake pad 44 nearest pivot 41 touches oralmost touches the perimeter surface of flywheel 12. The shaft 45 ofelongate screw 43 passes through bracket 13 and terminates in knob 30when the brake is not actuated. Bracket 13 and pivot 41 are fastenedsecurely to frame 5 (not shown) in any suitable manner. Flywheel 12 isfixed to front roller 3 as indicted in FIG. 1. To apply resistance tothe flywheel 12, the user turns knob 30 clockwise to elevate plate 42,which causes brake base 40 to urge brake pad 44 into increasing contactwith flywheel 12. Elongate screw 43 is made so that ten completeclockwise rotations of knob 30 will fully apply brake pad 44 to flywheel12. The amount of resistance generated is generally directly related tothe turns of the knob 30. Resistance is reduced by turning the knob 30counterclockwise. Brake pad 44 may be made of any suitable materialoffering some resilience and able to tolerate the friction generated.

The effect of the aggressive inertia is graphically illustrated in FIG.6. FIG. 6 shows the percentage of speed change for a single stride attwo different speeds (a typical walking speed and a typical runningspeed), over a wide range of slope. One important thing to note here iswhat happens when the deck is inclined at a slope steeper than 8.5degrees, as in the present invention. Basically, gravity is nowassisting the user to the point where the flywheel urges the belt tospeed up. However, the calculations of the graph are based only on theflywheel and a hypothetical user. There is also present an inherent“drag” from the contact of the belt on the rollers, the contact of theuser's feet on the belt (and the support surface under it), and the belttension both with and without the effect of the user's weight. The usercan easily achieve an equilibrium between the motion of the belt and theforce of his or her own stride, which can still vary over a wide rangeof speed with or without application of the brake. The user can, ofcourse, hold onto the handles 17, 28 or others, and/or can grasp siderails 20, while modifying his or her stride if desired or deemednecessary; the user may also simply step on the stationary sides offrame 5 next to the belt at any time.

The data for FIG. 6 were calculated using an average body weight of 175pounds and speeds of 3 miles per hour walking and 8 miles per hourrunning. Note that the inclination angle affects the percent change ofspeed more dramatically at a walking speed than it does at a runningspeed. This may seem counterintuitive, but the running speed value ishigher to begin with. The user will find that, with or without theappropriate application of the braking mechanism, the belt motion willnevertheless be both challenging and smooth. At a fixed slope of 12degrees, for example, the flywheel and braking mechanism are designed toprovide a full range of resistance and speeds.

FIG. 7 shows graphically the additional force required to maintain aconstant speed over the course of one stride, once the treadmill hasachieved the desired speed. Positive values indicate additional forceneeded from the user; negative values indicate that additional beltresistance is needed, Note that deck angles higher than 8.5 degreesagain show the need for additional resistance. Steady resistance iseasily provided by the brake system. Again, the calculations do notinclude factors of friction from the belt or other sources.

The versatility of the invention is illustrated in FIGS. 8 a to 8 f. Thebasic treadmill comprising frame 5, treadmill belt 1, and flywheel 12 isseen without attachments in FIG. 8 a. Attachment socket 6 is empty,ready for one of the attachments, but it is not necessary for a user toinstall one. Lift handles 50 and rollers 51 are provided so thetreadmill can readily be moved. FIG. 8 a shows knob 30 for controllingresistance by means of elongated screw 43 as shown in FIG. 5, but it maybe replaced by levered resistance control 13 (FIG. 8 b) as shown inFIG. 1. Each of the attachments shown in FIGS. 8 c, 8 d, and 8 e has astem 7 sized for secure insertion into attachment socket 6 andadjustable for height using pins 10. FIG. 8 d shows a sled padattachment. FIG. 8 e is a forearm attachment having an arm rest portion15. The shoulder harness attachment of FIG. 8 c in this case has anintermediate collar 60 for handles 28. The steer's horn attachment ofFIG. 8 f has an elongated socket 61 able to receive and fasten onto ashaft (not shown) extending from attachment socket 6. Other types ofattachments may be designed and easily attached to the treadmill.

This unit is eco-friendly, requires no external power and is made ofrecycled steel. The incline is fixed at an optimal position for cardioand muscle development. It has a wide range of resistance, features araised textured belt surface, and includes various front hand stations(attachments) that are adjustable to suit the user, particularly as toheight.

Thus it is seen that my invention includes a motorless treadmillcomprising (a) a frame, (b) a high front roller and a low rear rollerheld by the frame, (c) a continuous treadmill belt in contact with thefront and rear rollers, the treadmill belt having an outer surface andan inner surface, the inner surface in contact with the rollers, therollers and the treadmill belt defining an exercise surface inclined ata fixed angle of 9 to 20 degrees from the low rear roller to the highfront roller, (d) a flywheel fixed to the front roller, the flywheelhaving a radius of 7 to 10 inches and a perimeter weighted mass of 40 to60 pounds.

My invention also includes a motorless treadmill comprising (a) atreadmill frame including a front end and a rear end, the frameincluding a treadmill belt, a front roller on the front end, and a rearroller on the rear end, the front and rear rollers for enabling thetreadmill belt to turn, the treadmill frame including at least one frontsupport member fixedly elevating the front roller at an angle of 9 to 20degrees from the rear roller, (b) an elongate socket fixed to the frontend of the frame, the socket being adapted to receive and fix a shaft ofone or more interchangeable handles for grasping by a user to assume avariety of positions and apply a variety of muscles by a user, and (c) aperimeter weighted flywheel fixed to the front roller, the perimeterweighted flywheel having a mass of 40 to 60 pounds.

And, in another aspect, my invention includes a motorless treadmillhaving a fixed inclination of 9 to 20 degrees comprising (a) a frameincluding a socket for receiving an accessory shaft, and (b) a pluralityof accessory shafts adapted to fit securely in said socket and havinghandles deployed in various orientations.

I claim:
 1. A motorless treadmill comprising (a) a frame, (b) a highfront roller and a low rear roller held by said frame, (c) a continuoustreadmill belt in contact with said front and rear rollers, saidtreadmill belt having an outer surface and an inner surface, said innersurface in contact with said rollers, said rollers and said treadmillbelt defining an exercise surface inclined at a fixed angle of 9 to 20degrees from said low rear roller to said high front roller, (d) aflywheel fixed to said front roller, said flywheel having a radius of 7to 10 inches and a perimeter weighted mass of 40 to 60 pounds.
 2. Themotorless treadmill of claim 1 wherein said fixed angle of inclinationis in the range of 11 to 13 degrees.
 3. The motorless treadmill of claim1 including a brake operable by a user on said treadmill, said brakeincluding a brake pad for contacting said flywheel.
 4. The motorlesstreadmill of claim 1 wherein said mass of said flywheel is 45 to 55pounds,
 5. The motorless treadmill of claim 1 wherein said flywheelincludes a brake for said flywheel, said brake including a brake padadapted to contact said flywheel and a screw adapted to move said brakepad.
 6. The motorless treadmill of claim 1 wherein said flywheel isdirectly attached to said front roller so as to rotate with said frontroller.
 7. The motorless treadmill of claim 1 wherein said flywheel hastwo parts, said parts attached to opposite ends of the front roller,each part thereof having a radius of at least 7 inches, said parts eachhaving a mass of at least 20 pounds.
 8. The motorless treadmill of claim1 including an elongated socket mounted on the front of said frame, saidelongated socket adapted to receive and fix a shaft of one or moreinterchangeable accessory positioners.
 9. The motorless treadmill ofclaim 1 wherein said frame includes stationary shoulders next to saidexercise surface.
 10. A motorless treadmill comprising (a) a treadmillframe including a front end and a rear end, said frame including atreadmill belt, a front roller on said front end, and a rear roller onsaid rear end, said front and rear rollers for enabling said treadmillbelt to turn, said treadmill frame including at least one front supportmember fixedly elevating said front roller at an angle of 9 to 20degrees from said rear roller, (b) an elongate socket fixed to the frontend of said frame, said socket being adapted to receive and fix a shaftof one or more interchangeable handles for grasping by a user to assumea variety of positions and apply a variety of muscles by a user, and (c)a perimeter weighted flywheel fixed to said front roller, said perimeterweighted flywheel having a mass of 40 to 60 pounds.
 11. The motorlesstreadmill of claim 10 fixed at an incline between 11 and 13 degrees andwherein said flywheel has a radius 7 to 10 inches.
 12. The motorlesstreadmill of claim 10 including side rails mounted on the sides of saidframe.
 13. The motorless treadmill of claim 10 including a screwoperated brake pad for said flywheel.
 14. A motorless treadmill having afixed inclination of 9 to 20 degrees comprising (a) a frame including asocket for receiving an accessory shaft, and (b) a plurality ofaccessory shafts adapted to fit securely in said socket and havinghandles deployed in various orientations.
 15. The motorless treadmill ofclaim 14 including a flywheel adapted to provide inertial energy to saidtreadmill, said flywheel having a radius of 7 to 10 inches and aperimeter weighted mass of 40 to 60 pounds.
 16. The motorless treadmillof claim 14 wherein an accessory shaft (b) has an arm rest.